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Topic: Simple versus formal proof?
Replies: 34   Last Post: Jun 26, 2006 4:54 AM

 Messages: [ Previous | Next ]
 Ross Clement Posts: 569 Registered: 12/8/04
Re: Simple versus formal proof?
Posted: Jun 23, 2006 9:49 AM

Mohab wrote:
> for the last term to be even, one must assume that (k^2 + k) must be even,
> but that is what you are trying to prove.

Erm, this is the inductive step. The basis step is to show that k^2 + k
is even for some small value of k, such as 1.

1^ + 1 = 2 tick

Now show that if it holds for k it also holds for k+1

(k+1)^2 + (k+1)
= k^2 + k + 2k + 2 tick

I.e. we have the value for k, known to be even, plus 2(k+1), also even.
Surely in the induction step k^2 + k is the hypothesis, not the subgoal
to be proved?

Cheers,

Ross-c

Date Subject Author
6/23/06 Ross Clement
6/23/06 William Elliot
6/23/06 Ross Clement
6/23/06 William Elliot
6/23/06 Ross Clement
6/23/06 tamiry
6/23/06 Ross Clement
6/23/06 Robert Low
6/23/06 Ross Clement
6/23/06 Robert Low
6/23/06 The Qurqirish Dragon
6/23/06 Ross Clement
6/25/06 K. E. Pledger
6/26/06 Ross Clement
6/23/06 Bob Marlow
6/23/06 Ross Clement
6/23/06 Bob Marlow
6/23/06 Ross Clement
6/23/06 Bob Marlow
6/23/06 Robert Low
6/23/06 Bob Marlow
6/23/06 Ross Clement
6/23/06 Tom Smith
6/23/06 Tom Smith
6/23/06 Bob Marlow
6/23/06 Robert Low
6/23/06 Bob Marlow
6/23/06 Robert Low
6/24/06 Bob Marlow
6/23/06 tamiry
6/23/06 Justin
6/23/06 Tom Smith
6/23/06 Bob Marlow
6/23/06 Tom Smith
6/23/06 Bob Marlow